Star Tales – Taurus

Taurus is a distinctive constellation, with star-tipped horns and a head defined by a V-shaped group of stars. Two Greek bull-myths were associated with Taurus. Usually it was said to represent Zeus in the disguise he adopted for another of his extramarital affairs, this time as the bull that carried away Europa, daughter of King Agenor of Phoenicia.

Europa liked to play on the beach with the other girls of Tyre. Zeus instructed his son Hermes to drive the king’s cattle from their pastures on the mountain slopes towards the shore where the girls were playing. Adopting the shape of a bull, Zeus surreptitiously mingled with the lowing herd, awaiting his chance to abduct Europa. There was no mistaking who was the most handsome bull. His hide was white as fresh snow and his horns shone like polished metal.

Europa was entranced by this beautiful yet placid creature. She adorned his horns with flowers and stroked his flanks, admiring the muscles on his neck and the folds of skin on his flanks. The bull kissed her hands, while inwardly Zeus could hardly contain himself in anticipation of the final conquest. The bull lay on the golden sands and Europa ventured to sit on his back. At first, she feared nothing when the bull rose and began to paddle in the surf. But she became alarmed when it began to swim strongly out to sea. Europa looked around in dismay at the receding shoreline and clung tightly to the bull’s horns as waves washed over the bull’s back. Craftily, Zeus the bull dipped more deeply into the water to make her hold him more tightly still.

By now, Europa had realized that this was no ordinary bull. Eventually, the bull waded ashore at Crete, where Zeus revealed his true identity and seduced Europa. He gave her presents that included a dog that later became the constellation Canis Major. The offspring of Zeus and Europa included Minos, king of Crete, who established the famous palace at Knossos where bull games were held.

An alternative story says that Taurus may represent Io, another illicit love of Zeus, whom the god turned into a heifer to disguise her from his wife Hera. But Hera was suspicious and set the hundred-eyed watchman Argus to guard the heifer. Hera, furious at this, sent a gadfly to chase the heifer, who threw herself into the sea and swam away.

In the sky, only the front half of the bull is shown. This can be explained mythologically by assuming that the hind quarters are submerged. In reality, there is no space in the sky to show the complete bull, for the constellations Cetus and Aries lie where the bull’s hind quarters should be. Taurus shares with Pegasus this uncomfortable fate of having been sliced in half in the sky.

Taurus is depicted on star maps as sinking on one leg, perhaps to entice Europa onto its back. Manilius described the bull as lame and drew a moral from it: ‘The sky teaches us to undergo loss with fortitude, since even constellations are fashioned with limbs deformed’, he wrote.

The face of Taurus is marked by the V-shaped group of stars called the Hyades. Ovid in his Fasti asserts that the name comes from the old Greek word hyein, meaning ‘to rain’, so that Hyades means ‘rainy ones’, because their rising at certain times of year was said to be a sign of rain. In mythology the Hyades were the daughters of Atlas and Aethra the Oceanid. Their eldest brother was Hyas, a bold hunter who one day was killed by a lioness. His sisters wept inconsolably – Hyginus says they died of grief – and for this they were placed in the sky. Hence it seems equally likely that their name comes from their brother Hyas. In another story, the Hyades were nymphs who nursed the infant Dionysus in their cave on Mount Nysa, feeding him on milk and honey. The Romans had a different name; they called the Hyades suculae meaning ‘piglets’.

The mythographers were massively confused about the names and even the number of the Hyades. They are variously described as being five or seven in number. The Greek astronomer Ptolemy listed five Hyades in his star catalogue. Hyginus alone gives four different lists of their names, none of which agrees completely with the list of five originally given by Hesiod, viz: Phaesyle, Coronis, Cleia, Phaeo and Eudore. Astronomers have avoided the problem by not naming any of the stars of the Hyades.

Binoculars and small telescopes show many more members of the Hyades than are visible to the naked eye. In all, astronomers now estimate that several hundred stars belong to the cluster, which lies 150 light years away.

Even more famous than the Hyades is another star cluster in Taurus: the Pleiades, commonly known as the Seven Sisters. To a casual glance, the Pleiades cluster appears as a fuzzy patch like a swarm of flies over the back of the bull. According to Hyginus, some ancient astronomers called them the bull’s tail. So distinctive are the Pleiades that the ancient Greeks regarded them as a separate mini-constellation and used them as a calendar marker. Hesiod, in his agricultural poem Works and Days, instructs farmers to begin harvesting when the Pleiades rise at dawn, which in Greek times would have been in May, and to plough when they set at dawn, which would have been in November. Ptolemy did not list individual members of the Pleiades in his Almagest, giving only an indication of the cluster’s size.

In mythology the Pleiades were the seven daughters of Atlas and the oceanid Pleione, after whom they are named. One popular derivation is that the name comes from the Greek word plein, meaning ‘to sail’ – so Pleione means ‘sailing queen’ and the Pleiades are the ‘sailing ones’, because in Greek times they were visible all night during the summer sailing season. When the Pleiades vanished from the night sky, it was considered prudent to remain ashore. ‘Gales of all winds rage when the Pleiades, pursued by violent Orion, plunge into the clouded sea’, wrote Hesiod.

Alternatively, and possibly more likely, the name may come from the old Greek word pleos, ‘full’, which in the plural meant ‘many’, a suitable reference to the cluster. According to other authorities, the name comes from the Greek word peleiades, meaning ‘flock of doves’.

Unlike their half-sisters the Hyades, the names of all seven Pleiades are assigned to stars in the cluster: Alcyone, Asterope (also known as Sterope), Celaeno, Electra, Maia, Merope and Taygete. Two more stars are named after their parents, Atlas and Pleione. Alcyone is the brightest star in the cluster. According to mythology, Alcyone and Celaeno were both seduced by Poseidon. Maia, the eldest and most beautiful of the sisters, was seduced by Zeus and gave birth to Hermes; she later became foster-mother to Arcas, son of Zeus and Callisto. Zeus also seduced two others of the Pleiades: Electra, who gave birth to Dardanus, the founder of Troy; and Taygete, who gave birth to Lacedaemon, founder of Sparta. Asterope was ravished by Ares and became mother of Oenomaus, king of Pisa, near Olympia, who features in the legend of Auriga. Hence six Pleiades became paramours of the gods. Only Merope married a mortal, Sisyphus, a notorious trickster who was subsequently condemned to roll a stone eternally up a hill.

Although the Pleiades are popularly termed the Seven Sisters, only six stars are easily visible to the naked eye, and a considerable mythology has grown up to account for the ‘missing’ Pleiad. Eratosthenes says that Merope was the faint Pleiad because she was the only one who married a mortal. Hyginus and Ovid also recount this story, giving her shame as the reason for her faintness, but both add another candidate: Electra, who could not bear to see the fall of Troy, which had been founded by her son Dardanus. Hyginus says that, moved by grief, she left the Pleiades altogether, but Ovid says that she merely covered her eyes with her hand. Astronomers, however, have not followed either legend in their naming of the stars, for the faintest named Pleiad is actually Asterope.

Binoculars show dozens of stars in the Pleiades, and in all the cluster contains a hundred or so members. The Pleiades lie 380 light years away, two and a half times the distance of the Hyades. They are relatively youthful by stellar standards, the youngest being no more than a few million years old.

A famous myth links the Pleiades with Orion. As Hyginus tells it, Pleione and her daughters were one day walking through Boeotia when Orion tried to ravish her. Pleione and the girls escaped, but Orion pursued them for seven years. Zeus immortalized the chase by placing the Pleiades in the heavens where Orion follows them endlessly.

The bull’s glinting red eye is marked by the brightest star in Taurus, Aldebaran, a name that comes from the Arabic meaning ‘the follower’, referring to the fact that it follows the Pleiades across the sky. Surprisingly for such a prominent star, Greek astronomers had no name for it (although Ptolemy called it Torch in his Tetrabiblos, a book about astrology). Aldebaran appears to be a member of the Hyades but in fact is a foreground object at less than half the distance, and so is superimposed on the Hyades by chance. Aldebaran is a red giant star about 40 times the diameter of the Sun.

Marking the left horn of the bull is the star Alnath (also spelled Elnath), a name that comes from the Arabic meaning ‘the butting one’. Ptolemy described this star as being common with the right foot of Auriga, the Charioteer, but now it is the exclusive property of Taurus.

Near the tip of the bull’s right horn, the star Zeta Tauri, lies the remarkable Crab Nebula, the result of one of the most celebrated events in the history of astronomy – a stellar explosion, seen from Earth in AD 1054, that was bright enough to be visible in daylight for three weeks. We now know this this event was a supernova, the violent death of a massive star, and the Crab Nebula is the shattered remnant of the star that blew up. The Irish astronomer Lord Rosse gave the nebula its name in 1844 because he thought its shape resembled a crab when seen through his telescope. The Crab Nebula lies 6000 light years away, and appears as a misty patch through moderate-sized telescopes.